Axion pair creation by accelerated nuclei

We study the interaction between axions and nuclei by combining the Peccei-Quinn mechanism with results from QCD which imply that the QCD condensates are reduced within nuclear matter. Thus, the effective axion mass is also reduced, implying that nuclear matter acts as an effective medium for the axion field. Consequently, we find many analogies between nuclei and dielectric bodies, including a finite axion-nucleon scattering cross section with a characteristic momentum dependence given by the nuclear structure or a Casimir type attraction between two static nuclei with a specific distance dependence. Moreover, accelerated nuclei such as in ultraperipheral heavy-ion collisions can create entangled pairs of axions in analogy to the dynamical Casimir effect which can also be interpreted as signatures of the Unruh effect.